public class Sum extends Parent{
   
    static String b(){
        return "大哥好";
    }
    static class aa{
        public void aa(){
            System.out.println("我事一哥静态内部类");
        }
    }
    public static void main(String[] args) {
        Sum sum = new Sum();
        sum.a();
        System.out.println(Sum.b());


    }
}
